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91.
Barnett YA Eger K Eriksson S Folkers G Hansen PE Hofbauer R Komitowsky D Milon A Munch-Petersen B;European Thymidine Kinase Study Group 《Biotechnology advances》1994,12(4):663-668
A precondition for the chemotherapeutic treatment of a variety of virally-induced human diseases and malignant conditions is a highly selective interaction of the drug molecule to be used with it's biological target. To ensure the development of novel, effective drugs, it is essential that the biological target is well characterised with regard to it's structure and activity. Such characterisation relies upon adequate amounts of pure target being available. One of the most important enzymatic importers for antimetabolites is the enzyme thymidine kinase. In this article an in vitro protein expression system is described which facilitates the production of milligram amounts of pure and biologically active thymidine kinase, from a number of important biological sources. Results have shown that the in vitro produced enzyme has the exact biochemical propeties of the in vivo enzyme. Thus the in vitro protein expression system is an ideal vechicle to facilitate an in depth investigation of the enzyme's biological properties. 相似文献
92.
The c-fms proto-oncogene product is related to the receptor for the mononuclear phagocyte growth factor, CSF-1 总被引:234,自引:0,他引:234
The feline c-fms proto-oncogene product is a 170 kd glycoprotein with associated tyrosine kinase activity. This glycoprotein was expressed on mature cat macrophages from peritoneal inflammatory exudates and spleen. Similarly, the receptor for the murine colony-stimulating factor, CSF-1, is restricted to cells of the mononuclear phagocytic lineage and is a 165 kd glycoprotein with an associated tyrosine kinase. Rabbit antisera to a recombinant v-fms-coded polypeptide precipitated the feline c-fms product and specifically cross-reacted with a 165 kd glycoprotein from mouse macrophages. This putative product of the murine c-fms gene exhibited an associated tyrosine kinase activity in immune complexes, specifically bound murine CSF-1, and, in the presence of the growth factor, was phosphorylated on tyrosine in membrane preparations. The murine c-fms proto-oncogene product and the CSF-1 receptor are therefore related, and possibly identical, molecules. 相似文献
93.
Umberto Raucci Rossella Rossi Roberto Da Cas Concita Rafaniello Nadia Mores Giulia Bersani Antonino Reale Nicola Pirozzi Francesca Menniti-Ippolito Giuseppe Traversa Italian Multicenter Study Group for Vaccine Safety in Drug Children 《PloS one》2013,8(7)
Objective
Stevens-Johnson Syndrome (SJS) is one of the most severe muco-cutaneous diseases and its occurrence is often attributed to drug use. The aim of the present study is to quantify the risk of SJS in association with drug and vaccine use in children.Methods
A multicenter surveillance of children hospitalized through the emergency departments for acute conditions of interest is currently ongoing in Italy. Cases with a diagnosis of SJS were retrieved from all admissions. Parents were interviewed on child’s use of drugs and vaccines preceding the onset of symptoms that led to the hospitalization. We compared the use of drugs and vaccines in cases with the corresponding use in a control group of children hospitalized for acute neurological conditions.Results
Twenty-nine children with a diagnosis of SJS and 1,362 with neurological disorders were hospitalized between 1st November 1999 and 31st October 2012. Cases were more frequently exposed to drugs (79% vs 58% in the control group; adjusted OR 2.4; 95% CI 1.0–6.1). Anticonvulsants presented the highest adjusted OR: 26.8 (95% CI 8.4–86.0). Significantly elevated risks were also estimated for antibiotics use (adjusted OR 3.3; 95% CI 1.5–7.2), corticosteroids (adjusted OR 4.2; 95% CI 1.8–9.9) and paracetamol (adjusted OR 3.2; 95% CI 1.5–6.9). No increased risk was estimated for vaccines (adjusted OR: 0.9; 95% CI 0.3–2.8).Discussion
Our study provides additional evidence on the etiologic role of drugs and vaccines in the occurrence of SJS in children. 相似文献94.
Douglas Hayden Peter Lazar David Schoenfeld for The Inflammation the Host Response to Injury Investigators 《PloS one》2009,4(6)
We propose permutation tests based on the pairwise distances between microarrays to compare location, variability, or equivalence of gene expression between two populations. For these tests the entire microarray or some pre-specified subset of genes is the unit of analysis. The pairwise distances only have to be computed once so the procedure is not computationally intensive despite the high dimensionality of the data. An R software package, permtest, implementing the method is freely available from the Comprehensive R Archive Network at http://cran.r-project.org. 相似文献
95.
96.
S. Arunmozhi Balajee John W. Baddley Stephen W. Peterson David Nickle János Varga Angeline Boey Cornelia Lass-Fl?rl Jens C. Frisvad Robert A. Samson and the ISHAM Working Group on A. terreus 《Eukaryotic cell》2009,8(5):713-722
Phylogenetic analyses of sequences generated from portions of three genes coding for the proteins enolase (enoA), β-tubulin (benA), and calmodulin (calM) of a large number of isolates within the section Terrei, genus Aspergillus, revealed the presence of a new cryptic species within this section, Aspergillus alabamensis. Most members of this new cryptic species were recovered as colonizing isolates from immunocompetent patient populations, had decreased in vitro susceptibilities to the antifungal drug amphotericin B, and were morphologically similar to but genetically distinct from Aspergillus terreus isolates.Invasive infections caused by Aspergillus terreus are often disseminated with increased lethality compared with infections caused by other Aspergillus species and tend to be resistant to treatment with the antifungal drug amphotericin B (6, 14, 17). Despite the clinical significance of this organism, little is known about the epidemiology, genetic diversity, and population structure of A. terreus.Historically, A. terreus has been identified in the laboratory by conventional methods such as colony morphology and microscopic characteristics. Such morphological studies have placed A. terreus as a single homogenous species within the section Terrei along with two other varieties, A. terreus var. africanus and A. terreus var. aureus (11). Recent studies have shown that morphological characteristics may not be reliable for distinguishing Aspergillus species, as inferred from the demonstration of multiple cryptic species within the section Fumigati by molecular phylogenetic methods (3-5, 13, 18).In the past, molecular methods largely based on randomly amplified polymorphic DNA-PCR-based assays have shown that A. terreus isolates can have great strain diversity (1, 8, 16). One recent genotyping study of several A. terreus clinical isolates recovered from two different medical centers using this method concluded that nosocomial acquisition of A. terreus infections was highly unlikely given the great genetic diversity observed (7). Another study demonstrated that comparative sequence analyses of the D1 and D2 regions had limited utility to study relationships within the section Terrei, while the internal transcribed spacer regions were useful since there was more nucleotide diversity in this region (16). However, the authors of this study could not resolve species within the section Terrei using these molecular approaches.In the present study, we have developed a multilocus sequence approach employing three protein-coding regions to study species diversity of the section Terrei using a large panel of isolates from both clinical and environmental origins recovered from various parts of the world. The studies outlined below demonstrate the presence of a new, clinically relevant species, Aspergillus alabamensis, and clarify the taxonomic position of the A. terreus variant A. terreus var. aureus. 相似文献
97.
Ana Maria B. Menezes Rogelio Pérez-Padilla Fernando César Wehrmeister Maria Victorina Lopez-Varela Adriana Mui?o Gonzalo Valdivia Carmen Lisboa José Roberto B. Jardim Maria Montes de Oca Carlos Talamo Renata Bielemann Mariana Gazzotti Ruy Laurenti Bartolomé Celli Cesar G. Victora for the PLATINO team 《PloS one》2014,9(10)
Objective
To determine whether the presence of chronic obstructive lung disease (COPD) and reduction of lung function parameters were predictors of mortality in a cohort.Materials/Patients and Methods
Population based cohorts were followed in Montevideo, Santiago and Sao Paulo during 5, 6 and 9 years, respectively. Outcomes included all-cause, cardiovascular, respiratory and cancer mortality; exposures were COPD, forced expiratory volume in one second (FEV1) and forced vital capacity (FVC). Cox regression was used for analyses. Sensitivity, specificity, positive and negative predictive values, receiver operator characteristics curves and Youden''s index were calculated.Results
Main causes of death were cardiovascular, respiratory and cancer. Baseline COPD was associated with overall mortality (HR = 1.43 for FEV1/FVC<LLN; 2.01 for GOLD 2-4; 1.46 for GOLD 1-4; 1.50 for FEV1/FEV6 <LLN). For cardiovascular mortality, significant associations were found with GOLD 2-4 (HR = 2.68) and with GOLD 1-4 (HR = 1.78) for both genders together (not among women). Low FEV1 was risk for overall and respiratory mortality (both genders combined). FVC was not associated with overall mortality. For most COPD criteria sensitivity was low and specificity high. The area under the curve for FEV1 was greater than for FVC for overall and cardiovascular mortality.Answer to the Question
COPD and low FEV1 are important predictors for overall and cardiovascular mortality in Latin America. 相似文献98.
Rodrigo Pess?a Jaqueline Tomoko Watanabe Paula Calabria Alvina Clara Felix Paula Loureiro Ester C. Sabino Michael P. Busch Sabri S. Sanabani for the International Component of the NHLBI Recipient Epidemiology Donor Evaluation Study-III 《PloS one》2014,9(11)
Background
The findings of frequent circulation of HIV-1 subclade F1 viruses and the scarcity of BF1 recombinant viruses based on pol subgenomic fragment sequencing among blood donors in Pernambuco (PE), Northeast of Brazil, were reported recently. Here, we aimed to determine whether the classification of these strains (n = 26) extends to the whole genome sequences.Methods
Five overlapping amplicons spanning the HIV near full-length genomes (NFLGs) were PCR amplified from peripheral blood mononuclear cells (PBMCs) of 26 blood donors. The amplicons were molecularly bar-coded, pooled, and sequenced by Illumina paired-end protocol. The prevalence of viral variants containing drug resistant mutations (DRMs) was compared between plasma and PBMCs.Results
Of the 26 samples studied, 20 NFLGs and 4 partial fragments were de novo assembled into contiguous sequences and successfully subtyped. Two distinct BF1 recombinant profiles designated CRF70_BF1 and CRF71_BF1, with 4 samples in profile I and 11 in profile II were detected and thus constitute two novel recombinant forms circulating in PE. Evidence of dual infections was detected in four patients co-infected with distinct HIV-1 subtypes. According to our estimate, the new CRF71_BF1 accounts for 10% of the HIV-1 circulating strains among blood donors in PE. Discordant data between the plasma and PBMCs-virus were found in 15 of 24 donors. Six of these strains displayed major DRMs only in PBMCs and four of which had detectable DRMs changes at prevalence between 1-20% of the sequenced population.Conclusions
The high percentage of the new RF71_BF1 and other BF1 recombinants found among blood donors in Pernambuco, coupled with high rates of transmitted DRMs and dual infections confirm the need for effective surveillance to monitor the prevalence and distribution of HIV variants in a variety of settings in Brazil. 相似文献99.
Shashank R. Joshi Ranjit Mohan Anjana Mohan Deepa Rajendra Pradeepa Anil Bhansali Vinay K. Dhandania Prashant P. Joshi Ranjit Unnikrishnan Elangovan Nirmal Radhakrishnan Subashini Sri Venkata Madhu Paturi Vishnupriya Rao Ashok Kumar Das Tanvir Kaur Deepak Kumar Shukla Viswanathan Mohan for the ICMR– INDIAB Collaborative Study Group 《PloS one》2014,9(5)
Aim
To study the pattern and prevalence of dyslipidemia in a large representative sample of four selected regions in India.Methods
Phase I of the Indian Council of Medical Research–India Diabetes (ICMR-INDIAB) study was conducted in a representative population of three states of India [Tamil Nadu, Maharashtra and Jharkhand] and one Union Territory [Chandigarh], and covered a population of 213 million people using stratified multistage sampling design to recruit individuals ≥20 years of age. All the study subjects (n = 16,607) underwent anthropometric measurements and oral glucose tolerance tests were done using capillary blood (except in self-reported diabetes). In addition, in every 5th subject (n = 2042), a fasting venous sample was collected and assayed for lipids. Dyslipidemia was diagnosed using National Cholesterol Education Programme (NCEP) guidelines.Results
Of the subjects studied, 13.9% had hypercholesterolemia, 29.5% had hypertriglyceridemia, 72.3% had low HDL-C, 11.8% had high LDL-C levels and 79% had abnormalities in one of the lipid parameters. Regional disparity exists with the highest rates of hypercholesterolemia observed in Tamilnadu (18.3%), highest rates of hypertriglyceridemia in Chandigarh (38.6%), highest rates of low HDL-C in Jharkhand (76.8%) and highest rates of high LDL-C in Tamilnadu (15.8%). Except for low HDL-C and in the state of Maharashtra, in all other states, urban residents had the highest prevalence of lipid abnormalities compared to rural residents. Low HDL-C was the most common lipid abnormality (72.3%) in all the four regions studied; in 44.9% of subjects, it was present as an isolated abnormality. Common significant risk factors for dyslipidemia included obesity, diabetes, and dysglycemia.Conclusion
The prevalence of dyslipidemia is very high in India, which calls for urgent lifestyle intervention strategies to prevent and manage this important cardiovascular risk factor. 相似文献100.
Methods for surveillance of fetal alcohol syndrome: The fetal alcohol syndrome surveillance network II (FASSNetII) – Arizona,Colorado, New York, 2009 ‐ 2014 下载免费PDF全文
Leslie A. O'Leary Linnette Ortiz April Montgomery Deborah J. Fox Christopher Cunniff Margaret Ruttenber April Breen Sydney Pettygrove Don Klumb Charlotte Druschel Jaime L. Frías Luther K. Robinson Jacquelyn Bertrand Kelly Ferrara Maureen Kelly Suzanne M. Gilboa F. John Meaney for the FASSNetII 《Birth defects research. Part A, Clinical and molecular teratology》2015,103(3):196-202